This invention relates to protein interaction detection systems.
Genetic analysis is a tool for understanding the protein networks that govern biological processes. The manipulations performed by geneticists (e.g., staging of temperature sensitive mutants, construction and analysis of double mutants, and generation and observation of F1 and F2 progeny) define relationships between genes. These abstract relationships between genes often reflect underlying biological realities. For example, the epistasis relation may suggest that one gene normally acts on another to cause a phenotype, the allelic specific suppression relation may suggest that two gene products physically interact (Hartman and Roth, Adv. Genet. 17:1-105 (1973); Jarvik and Botstein, Proc. Natl. Acad. Sci. USA 70:2046-50 (1973)), and the dependency relation may suggest that the action of one gene product precedes that of another in time (Hereford and Hartwell, J. Mol. Biol. 84:445-61 (1974)).
Information obtained from these genetic manipulations is typically of very high quality, but is often relatively difficult to acquire. The recent increase in the rate of identification of new coding sequences has renewed interest in global systematic methods to understand gene function. These methods include the “two hybrid” or “interaction trap” methods which have been developed to assay contact between a single bait and interacting proteins (Fields and Song, Nature 340:245-6 (1989); Chien et al., Proc. Natl. Acad. Sci. USA 88:9578-82 (1991); Gyuris et al., Cell 75:791-803 (1993); Durfee et al., Genes Dev. 7:555-69 (1993); Estojak et al., Mol. Cell. Biol. 15:5820-9 (1995). Contact between two proteins in these systems defines a physical relationship that is frequently of biological significance.